Dear All, Our mobile device, which runs linux 2.4, uses ext3 as its filesystem. To make ext3 work, we have Samsung's xrs module, a middle layer which resembles MTD, to simulate disk devices over Samsung's onenand flash. Recently some of our phones are suffering a filesystem crash with only 30% space used on that partition. So I began to doubt whether it is right to employ an disk filesystem on an embedded system. It seems the kjournald kernel thread sends out an oops. Just assuming the xrs layer simulates perfectly a real disk device, I want to discuss what the disadvantages or advantages, if there is any, are in such a design. I think the point is that to keep ext3 safe, we must umount these devices cleanly before rebooting to let the kernel flush useful information to the disks. On a PC we don't do many reboots. Even dirty reboots without umount happen, data are very likely to be recovered. And yet we have experienced administrators and uitilities like e2fsck to resort to. But even then there are still chances that disks could fail. Embedded systems are quite different. Developers and customers could pull out the battery at all times. It's unpredictable. Consequently there should be much more chances than on a PC that a disk failure happen. And we can't bet on the customers. Once the products are delivered to our customers, any disk failure, either recoverable(I think it's the most cases) or unrecoverable, is unacceptable. We can't expect the customers do what we are supposed to do. Guys, I really want polish the products as much as I can. Please give your comments on what kind of risks we may take by using ext3 in such a design. And if you have rich experience of using ext3 in an embedded system, great, please feel free to share it. Any helps are appreciated. -- Best Regards, Alvin Cao _______________________________________________ Ext3-users mailing list Ext3-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/ext3-users
